# Converging Lenses and Magnification

• mikezhou

#### mikezhou

I'm in the middle of studying for the MCAT, and just want to get all the concepts instead of memorizing how to solve problems. I'm having a hard time understanding converging lenses.

From what I understand, converging lenses create real images that are inverted. This property of inversion means that the magnification should be negative, where m = - (i / o). Since the image (i) is a positive number (real) and the object is a negative number (other side of lens), how is it possible that m is negative? i.e. - (positive/negative) = positive

What am I missing here?

Last edited:
mikezhou said:
Since the image (i) is a positive number (real) and the object is a negative number (other side of lens), how is it possible that m is negative?
The usual sign convention (there are several) treats object distances as positive if the object is in front of the lens (as usual).

## 1. What is a converging lens?

A converging lens is a convex lens that is thicker in the middle and thinner at the edges. It is designed to bring parallel rays of light together at a single point, known as the focal point. This type of lens is commonly used in magnifying glasses, cameras, and telescopes.

## 2. How does a converging lens magnify an object?

A converging lens magnifies an object by bending the light rays that pass through it. This bending of light causes the image to appear larger than the actual object. The amount of magnification depends on the shape and curvature of the lens, as well as the distance between the object and the lens.

## 3. What is the formula for calculating magnification in a converging lens?

The formula for calculating magnification in a converging lens is M = hi/ho = -di/do, where M is the magnification, hi is the image height, ho is the object height, di is the image distance, and do is the object distance. It is important to note that the magnification is a ratio and has no units.

## 4. Can a converging lens produce both real and virtual images?

Yes, a converging lens can produce both real and virtual images. A real image is formed when the light rays actually converge at a point, while a virtual image is formed when the light rays only appear to be coming from a specific location. The location of the image depends on the position of the object and the focal length of the lens.

## 5. What factors affect the magnification of a converging lens?

The magnification of a converging lens is affected by several factors, including the focal length of the lens, the distance between the object and the lens, and the size of the object. Additionally, the type of lens and the material it is made of can also affect the magnification. Finally, the angle at which the light rays enter the lens can also impact the resulting magnification.